A landmark international study has found that the genetic drivers of Parkinson’s disease can vary dramatically between populations, underscoring the need to include people of various ancestries in genetic research and clinical trials. The study, published in The Lancet Neurology, analyzed genetic data from 99,783 participants in the Global Parkinson’s Genetics Program, including 58,559 people with Parkinson’s disease and 41,224 people without the disease. Investigators examined known Parkinson’s disease-causing mutations and high-risk variants across 11 ancestry groups, making it the largest and most genetically diverse Parkinson’s study conducted to date. “About three out of every four genetic studies of Parkinson’s disease have focused on this one group, even though Parkinson’s affects people all over the world.” “It directly affects whether new Parkinson’s treatments will actually work for, and be available to, patients around the world.”